Arginine bicarbonate has use in various industrial applications, including use in personal care compositions, e.g., oral care compositions. See e.g., U.S. Pat. No. 6,524,558. As the industrial requirements for arginine bicarbonate increases, so will the need for improved processes and methods to manufacture the same.
Arginine bicarbonate may be produced by bubbling carbon dioxide gas through a saturated arginine aqueous solution. However, the efficiency of the existing process needs to be improved. The existing process is slow, requiring 24 to 48 hours to complete the reaction. Carbon dioxide has very limited solubility in water, and releasing the gas into the solution produces a maximum concentration of about 1.2×10−5 M at room temperature and its natural partial pressure (3.5×10−4 atmosphere). The solubility of arginine in water is only about 15% weight/weight at room temperature. Producing a concentrated arginine bicarbonate solution (e.g., about 40%) requires the continual addition of arginine to the solution, thereby increasing production time and requires constant monitoring of the reaction. Thus there is a need to improve methods to manufacture arginine bicarbonate.